Fig. 5

MSC therapy promotes parenchymal repair in Scnn1b-Tg mice. Mice were given 5 × 10⁵ MSCs intravenously at 4 and 6 weeks of age before tissue analysis at 8 weeks. (a) Analysis of proliferation in parenchymal tissue using Ki67 immunohistochemistry, representative images shown, black arrows indicate positively stained nuclei, 3LL-Lewis Carcinoma tumor xenograft used as a positive control for Ki-67 staining, image scale bars 50 µm. (b) Quantification of the % of Ki67 positive cells in MSC and vehicle treated Scnn1b-Tg lung parenchyma. Data represents average counts ± SEM from ≥ 10 fields of view per mouse, with n ≥ 7 mice per group. Statistical analysis was performed using unpaired or Mann–Whitney t-test as appropriate, with * = P ≤ 0.05. (c) Immunofluorescent staining of lung parenchymal tissue 24 h post MSC administration. Cryosections (8 µm) were co-stained with Dapi (blue), Prosurfactant Protein C (SPC) (red) and ki67 (green). White arrows on representative images represent SPC⁺Ki67⁺Dapi⁺ cells, scale bars 50 µm. (d) Quantification of IF staining 24 h post MSC administration, where data represents average counts ± SEM from 4–6 fields of view per mouse, with n = 6 mice per group. Statistical analysis was performed using Mann–Whitney t-test with * = P ≤ 0.05.